Tesamorelin
Tesamorelin is a synthetic GHRH (growth-hormone-releasing hormone) analog approved by the FDA as Egrifta/Egrifta SV/Egrifta WR for reduction of excess visceral abdominal fat in HIV-infected adults with lipodystrophy. It works by stimulating the pituitary to release growth hormone, which lowers visceral adipose tissue without a general weight-loss effect.
Tesamorelin reconstitution calculator
Open full calculator →Typical dosing
| Goal | Range | Route | Frequency |
|---|---|---|---|
| HIV-associated lipodystrophy (label, Egrifta SV) | 1.4 mg | SubQ (abdomen, rotate sites) | once daily |
| HIV-associated lipodystrophy (label, Egrifta WR) | 1.28 mg | SubQ (abdomen, rotate sites) | once daily |
Ranges compiled from research literature — not a prescription.
How it works
Tesamorelin is a 44-amino-acid analog of native GHRH, modified with an N-terminal trans-3-hexenoic acid group that resists enzymatic (DPP-4) degradation and extends its activity relative to endogenous GHRH. It binds GHRH receptors on pituitary somatotroph cells, a Gs-coupled pathway that raises cAMP and triggers calcium-dependent, pulsatile release of growth hormone — mirroring the body's natural GH secretion pattern rather than delivering GH directly.
The downstream GH pulses raise circulating IGF-1 and, in HIV-infected patients with abdominal fat accumulation, produce a measurable reduction in visceral adipose tissue (VAT). This is the basis of the only approved indication: a pooled analysis of two 26-week phase 3 trials (n=806) reported meaningful VAT reduction with tesamorelin 2 mg/day versus placebo, and a separate randomized trial (Stanley et al., JAMA 2014) found tesamorelin reduced VAT by roughly 9.9% versus a 6.6% increase with placebo, along with modest reductions in liver fat, without worsening glucose or lipid parameters in that population.
It is important to be precise about scope: the FDA approval and this trial evidence are specific to HIV-associated lipodystrophy — a distinct metabolic condition tied to antiretroviral therapy and HIV infection itself. Use of tesamorelin for general anti-aging, bodybuilding, or fat loss in people without HIV lipodystrophy is off-label and has not been evaluated in the same rigorous, FDA-reviewed trials; efficacy and safety in that population are not established by the approved label.
Because tesamorelin acts upstream (on the pituitary) rather than supplying GH directly, its effects depend on an intact hypothalamic-pituitary axis — which is also why pituitary axis disruption is a contraindication, and why its GH/IGF-1 stimulating effect carries the same theoretical long-term considerations (e.g., malignancy risk, IGF-1-related effects) associated with other GH-axis therapies.
Side effects & safety
- Fluid retention is common and can present as edema, arthralgia, myalgia, or carpal tunnel syndrome, especially early in treatment.
- Because tesamorelin raises IGF-1, the FDA label calls for monitoring IGF-1 levels during therapy and considering discontinuation with persistent elevation, given unknown long-term effects of sustained elevation.
- Glucose intolerance can occur; the label recommends evaluating glucose before and during treatment, with added caution in patients with diabetes or prediabetes.
- Contraindicated in active malignancy — pre-existing malignancy must be inactive and treatment complete before starting.
- Contraindicated in pregnancy and in patients with disruption of the hypothalamic-pituitary axis (pituitary surgery, radiation, tumor) or hypersensitivity to tesamorelin/excipients.
- Injection-site reactions and paresthesias are among the most common adverse effects; this profile and all dosing above reflect the FDA-approved use only — it does not extend to unapproved (off-label) uses.
Research
Primary sources — PubMed.
- FDA. EGRIFTA SV (tesamorelin for injection) Prescribing Information. https://www.accessdata.fda.gov/drugsatfda_docs/label/2019/022505s012s013lbl.pdf
- DailyMed. EGRIFTA SV label. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=3d783378-b02d-4f19-99dd-0fc91a042224
- Falutz J, et al. Effects of tesamorelin on visceral fat: pooled analysis of two phase 3 trials. J Clin Endocrinol Metab. 2010. https://academic.oup.com/jcem/article-abstract/95/9/4291/2835394
- Stanley TL, et al. Effect of Tesamorelin on Visceral Fat and Liver Fat in HIV-Infected Patients. JAMA. 2014. https://pmc.ncbi.nlm.nih.gov/articles/PMC4363137/
- Tesamorelin. LiverTox, NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK548730/
- ClinicalTrials.gov. TH9507 in Patients With HIV-Associated Lipodystrophy. NCT00123253. https://clinicaltrials.gov/study/NCT00123253